By Robert Ellison. Updated on Thursday, December 26, 2019.
I'm slowly converting a number of blogs from Blogger to BlogEngine.NET. The least fun part is dealing with the Blogger export file. For this blog I used a Powershell script but had problems with comments not exporting correctly and it was quite painful to fix everything up. Blogger allows you to export a copy of your blog using ATOM, however BlogEngine.NET (and other tools) speak BlogML.
I've just released a command line tool that takes the ATOM format Blogger export and converts it to BlogML. You can download Blogger2BlogML from GitHub. The tool uses .NET 4.0 (client profile) so you'll need to install this if you don't already have it. If you give Blogger2BlogML a try let me know how you get on.
(Published to the Fediverse as:
Converting Blogger ATOM export to BlogML #code#blogger#blogml#codeplex#c##.net Tool that converts Blogger ATOM blog export files to BlogML for importing to a different blog engines.)
I've just released a small update for my ESRI Shapefile Reader project on GitHub. The only change is a patch from SolutionMania that fixes a problem when the shapefile name is also a reserved name in the metadata database. The patch escapes the name preventing an exception from being thrown.
Catfood.Shapefile.dll is a .NET 2.0 forward only parser for reading an ESRI Shapefile. Download 1.20 from GitHub.
By Robert Ellison. Updated on Thursday, November 12, 2015.
The Volume Shadow Copy Service (VSS) takes a snapshot of an NTFS drive at a point in time. The clever thing about VSS is that it doesn't copy anything — it starts with the assumption that nothing has changed and then keeps track of every change to the snapshot so only changes need to be stored.
From Windows Vista on it's possible to mount a shadow copy as a drive letter or share. ShadowTask is a command line tool that creates a VSS copy, mounts it as a drive and then runs a program or batch file. For example:
ShadowTask C V dostuff.bat
Creates a copy of C:, mounts it as V: and then runs dostuff.bat.
Let's say you want to copy a locked file — maybe some outlook personal folders. Dostuff.bat could contain:
The ZIP contains both 32 and 64 bit versions of the tool. You must use the version that matches your platform. ShadowTask supports Windows Vista and 7. XP doesn't support mounting a shadow copy so ShadowCopy will fail if you try to use it on XP. ShadowCopy must run as admin (elevated).
(Published to the Fediverse as:
Do useful things with the volume shadow copy service (VSS) #code#vss ShadowTask mounts a volume shadow copy to a drive letter using VSS and then lets you run a batch file (maybe to copy a locked file or backup the entire drive))
PdfScan is a simple tool for scanning pages into a PDF file. You can scan single pages from a flatbed scanner or several pages from a document feeder. The page size applies to both the scan and the page(s) added to the PDF.
I wrote PdfScan because I know I'm going to be scanning a lot of documents over the next couple of weeks. Previously I used a tool called ScanToPDF from O Imaging but their licensing pissed me off so much that I'd rather waste time reinventing the wheel than pay them for another copy.
This is a beta — it works with my scanner and my documents. There's no installer, so extract the ZIP file and run the EXE to use it. PdfScan requires the .NET 4.0 Framework. If you get an error when you run PdfScan.exe try installing .NET 4 and then run it again.
If enough people use this I'll make it a bit more friendly, add an installer and release it through Catfood. If you like it leave a comment below. If it doesn't work for you leave a comment or email me and I'll try to help.
(Update September 12, 2010: I've tided PdfScan up and released it through Catfood Software. Download from Catfood PdfScan.)
I've been going nuts trying to scan from the document feeder on my Canon imageClass MF4150. Everything worked as expected from the flatbed, no dice trying to persuade the ADF to kick in. I found some sample code but it was oriented towards devices that can detect when a document is available in the feeder. Evidently my Canon doesn't expose this and so needs to be told the source to use.
The way to do this is to set the WIA_DPS_DOCUMENT_HANDLING_SELECT property to FEEDER. You then read WIA_DPS_DOCUMENT_HANDLING_STATUS to check that it's in the right mode and initiate the scan. This did not work for toffee.
After much experimentation I discovered a solution. I had been setting device properties and then setting item properties before requesting the scan. Switching the order - item then device - made everything work.
Here's the function to scan one page:
A few notes — XImage is a type from PDFSharp. I wrote this as part of a PDF scanner that I'll post next so the scanned images are saved and then loaded into an XImage for rendering to the PDF document. The magic numbers come from WiaDef.h in the Platform SDK. If the ADF is out of pages this method sets the return image to null and eats the exception. This is because the function is called repeatedly to scan in pages until the ADF is empty if _adf is true (otherwise it grabs one image from the flatbed).
If you've been banging your head against a wall trying to get WIA to work with a document feeder I hope this helps.
Catfood PdfScan 1.40 is a small bug fix release. PdfScan converts documents to PDFs with the help of a flatbed or automatic document feeder (ADF) scanner.
Scanning multiple pages into a PDF file
PdfScan is a simple tool for scanning pages into a PDF file. You can scan single pages from a flatbed scanner or several pages from a document feeder. The page size applies to both the scan and the page(s) added to the PDF.
I wrote PdfScan because I know I'm going to be scanning a lot of documents over the next couple of weeks. Previously I used a tool called ScanToPDF from O Imaging but their licensing pissed me off so much that I'd rather waste time reinventing the wheel than pay them for another copy.
This is a beta — it works with my scanner and my documents. There's no installer, so extract the ZIP file and run the EXE to use it. PdfScan requires the .NET 4.0 Framework. If you get an error when you run PdfScan.exe try installing .NET 4 and then run it again.
If enough people use this I'll make it a bit more friendly, add an installer and release it through Catfood. If you like it leave a comment below. If it doesn't work for you leave a comment or email me and I'll try to help.
(Update September 12, 2010: I've tided PdfScan up and released it through Catfood Software. Download from Catfood PdfScan.)
By Robert Ellison. Updated on Saturday, September 29, 2018.
After floundering a bit with the WPF Dispatcher I've come up with a simple way to make sure an event handler executes on the UI thread without paying the overhead of always invoking a delegate.
This has the benefit (for me at least) of being very easy to remember. Hook up the event handler and then if there's a chance it could be called from a different thread wrap it using the pattern above. It's easier to read than an anonymous delegate and much faster than defining a specific delegate for the event in question.
I haven't tested the various methods to see which is the fastest yet… will get round to this at some point.
(Published to the Fediverse as:
Use WPF Dispatcher to invoke event handler only when needed #code#wpf#tips How to Invoke or BeginInvoke an event handler to the UI thread using the WPF Dispatcher.)
By Robert Ellison. Updated on Saturday, September 29, 2018.
When testing out a WPF app on XP I got an unhelpful XamlParseException error report.
I was a little puzzled because I was hooking up error reporting in App.xaml.cs:
My error handler was attempting to create a XAML window to report the error, and evidently this was bombing out as well triggering the good doctor Watson. I added a MessageBox call instead and discovered that the XamlParseException was wrapping a FileFormatException and the stack trace indicated that the problem was with setting the icon for the window. After removing the icon the app started up fine. Weird.
It turns out that WPF chokes on a compressed 256x256 icon on XP and Vista (Windows 7 seems to cope fine). Saving the icon without compression fixes the problem. I use IcoFX and you can set this at Options -> Preferences -> Options -> Compress 256x256 images for Windows Vista. Of course the consequence is that the icon is a couple of hundred kilobytes larger.
(Published to the Fediverse as:
XamlParseException and 256x256 icons #code#xaml#wpf#wtf You can't use a compressed 256x256 icon with WPF but you can include an uncompressed version.)
I've spent the last day learning how to use OAuth and XAuth to post to Twitter. There are rumblings that Twitter will start to phase out basic authentication later this year, and more importantly you can only get the nice “via...” attribution if you use OAuth (for new apps, old ones are grandfathered in).
I coded up my own OAuth implementation, referring to Twitter Development: The OAuth Specification on Wrox and the OAuthBase.cs class from the oauth project on Google Code. Both are great references, but both fail with multibyte characters. The problem is that each byte needs to be separately escaped. OAuthBase.cs encodes characters as ints rather than breaking out the bytes and the Wrox article incorrectly suggests using Uri.EscapeDataString().
Here's a method to correctly encode parameters for OAuth:
NoEncode chars is a list of the permitted characters:
An impact of this encoding is that spaces must be encoded as %20 rather than plus. I was worried that each space would end up counting as three characters towards the 140 character limit. I tested this and it isn't true, so use HttpUtility.UrlEncode() to calculate the number of characters in the post OAuthUrlEncode() or similar to actually encode post parameter.
(Published to the Fediverse as:
Space and multibyte character encoding for posting to Twitter using OAuth #code#twitter#oauth#xauth How to encode spaces and multibyte characters when posting to Twitter via OAuth / XAuth.)
By Robert Ellison. Updated on Wednesday, February 22, 2017.
I finished off my BlogEngine.NET migration yesterday missing a couple of useful sections from the previous incarnation of this blog. The first is a list of the most popular posts based on Google Analytics data. I've just finished porting this from a UserControl to a widget for BlogEngine.NET. To use this just download and extract this zip file to your widgets directory:
You can see the widget in action under the Most Popular heading to the left if you're reading this post on the blog.
Most of the settings should be pretty obvious. The Google Analytics profile is the exception. This isn't the ID included in your tracking code. To get the profile log in to Google Analytics and click Edit next to the profile you want to use. At the top of the page you'll see a Profile ID. You need to use this number prefixed by ga: (i.e. ga:1234567). Once you have this and your account credentials entered you should be up and running.
The Post must match settings is a regular expression used to filter the Google Analytics report to only include blog posts. The default value corresponds to a default BlogEngine.NET install and only includes pages that start .../post/ (the regular expression is ^/post/). If your posts are under .../blog/posts/ then just update accordingly (^/blog/posts/). If you want to include the most popular pages regardless of the path just leave this setting blank.
If you have any questions or feature requests leave a comment below.
(Published to the Fediverse as:
BlogEngine.NET most popular pages widget using Google Analytics #code#blogengine.net#googleanalytics A BlogEngine.NET most popular posts widget using data from the Google Analytics API.)